Asynchronous Method: AsyncResolve.cs program

The AsyncResolve.cs program

using System;
using System.Drawing;
using System.Net;
using System.Text;
using System.Windows.Forms;
class AsyncResolve    Form:
{
  TextBox address;
  ListBox results;
  private AsyncCallback OnResolved;
  public AsyncResolve()
  {
   Text = "DNS Address Resolver";
   Size = new Size(400,380);
   OnResolved = new AsyncCallback(Resolved);
   Label label1 = new Label();
   label1.Parent = this;
   label1.Text = "Enter address to resolve:";
   label1.AutoSize = true;
   label1.Location = new Point(10, 10);
   address = new TextBox();
   address.Parent = this;
   address.Size = new Size(200, 2 * Font.Height);
   address.Location = new Point(10, 35);
   results = new ListBox();
   results.Parent = this;
   results.Location = new Point(10, 65);
   results.Size = new Size(350, 20 * Font.Height);
   Button checkit = new Button();
   checkit.Parent = this;
   checkit.Text = "Resolve";
   checkit.Location = new Point(235,32);
   checkit.Size = new Size(7 * Font.Height, 2 * Font.Height);
   checkit.Click += new EventHandler(ButtonResolveOnClick);
  }
  void ButtonResolveOnClick(object obj, EventArgs ea)
  {
   results.Items.Clear();
   string addr = address.Text;
   Object state = new Object();
   Dns.BeginResolve(addr, OnResolved, state);
  }
  private void Resolved(IAsyncResult ar)
  {
   string buffer;
   IPHostEntry iphe = Dns.EndResolve(ar);
   buffer = "Host name: " + iphe.HostName;
   results.Items.Add(buffer);
   foreach(string alias in iphe.Aliases)
   {
     buffer = "Alias: " + alias;
     results.Items.Add(buffer);
   }
   foreach(IPAddress addrs in iphe.AddressList)
   {
     buffer = "Address: " + addrs.ToString();
     results.Items.Add(buffer);
   }
  }
  public static void Main()
  {
   Application.Run(new AsyncResolve());
  }

}